Induced drag is the portion of aerodynamic drag that appears only because a wing (or other surface) is generating lift; it is often called “drag due to lift.”

Quick Scoop: What Is Induced Drag?

When a wing makes lift, pressure is lower on top and higher on the bottom.

Air naturally tries to move from high pressure (below) to low pressure (above) by curling around the wingtips, creating swirling wingtip vortices that trail behind the aircraft.

These vortices push the airflow behind the wing slightly downward (downwash).

Downwash tilts the overall lift vector slightly backward, so a small component of what “should” be pure lift now points opposite the direction of flight: that rearward component is induced drag.

In equation form, the lift-induced drag coefficient is often written as something like CD,i=k⋅CL2C_{D,i}=k\cdot C_L^2CD,i​=k⋅CL2​, meaning induced drag increases with the square of the lift coefficient.

Key facts in bullet form

  • Induced drag is an inevitable byproduct of producing lift on a finite wing.
  • It comes from wingtip vortices, downwash, and the backward tilt of the lift vector.
  • It is strongest at low speeds and high angles of attack (takeoff, climb, landing, heavy weight).
  • It decreases sharply as airspeed increases (for the same weight and configuration).
  • It can be reduced by long, slender wings (high aspect ratio) and winglets, which weaken the vortices.

Tiny story to visualize it

Imagine a small airliner on final approach, flying slowly with its nose slightly up and flaps extended to stay aloft.
Behind its wingtips, you could almost “see” the swirling tubes of air rolling away as vortices, especially on a humid day.

Those invisible spirals bend the airflow downward and tip the lift vector back, so the engines must work harder just to maintain that slow, high-lift flight — that extra power is paying for induced drag.

TL;DR: Induced drag = drag that exists because lift is being generated, caused by wingtip vortices and downwash tilting lift slightly backward, largest at low speed/high angle of attack and reduced by better wing design.

Information gathered from public forums or data available on the internet and portrayed here.